Set 151 to win at Sydney's Drummoyne Oval, Tahlia Wilson's unbeaten 55 from 44 balls helped the Thunder cruise to victory with 10 balls to spare.
Phoebe Litchfield then finished the game with a big six to bring up her 35-ball half-century, while Georgia Voll hit 43 from 31 at the top.
Beaten in their first three games, the Thunder remain seventh on the table but are now back in the hunt ahead of their clash with last-placed Brisbane on Friday.
After being given a life early when Freya Kemp put down a sitter when on five, Thunder opener Wilson was clinical from there on.
She sat at the other end while Voll was the main aggressor, before taking over the innings when the right-hander was caught behind.
Leading run-scorer in the 50-over WNCL last summer, Wednesday's knock marked only Wilson's third half-century in 80 WBBL games.
Earlier Katie Mack threatened to make the Thunder pay for a missed chance of their own, when the Perth opener was dropped first ball at slip by Heather Knight before reaching 79.
She hit Voll for three straight boundaries a few overs later, kicking off an innings where she drove through the covers at will and pulled the ball to the boundary regularly.Â
Signed by the Scorchers to offer more support to Beth Mooney, it was Mack that was the lead act on Wednesday night.
But no other Scorcher passed 20, with the innings stagnating when Kemp was run out and Paige Schofield trapped lbw in the space of two balls in the 12th over.
That ultimately proved decisive with the Scorchers' 7-150 never looking like enough once the Thunder got going.
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